Electric snap switch

ABSTRACT

An electric snap switch having a snap-acting mechanism for shifting a permanent magnet to operate a reed switch which is always positioned within the effective magnetic flux of the magnet so as to open the reed switch by applying vertically generated magnetic flux and to close reed switch by applying the horizontally generated magnetic flux upon displacement of the magnet by means of the snap action of the snap-acting mechanism, resulting in that the shifting stroke of the magnet is reduced to improve the sensitivity and endurance of the switch.

United. States Patent Inventor Yasuhiko Iwarni Kyoto, Japan Appl. No. 879,706 Filed Nov. 25, 1969 Patented Oct. 5, 1971 Assignee Omron Tateisi Electronics Co.

Kyoto, Japan Priority Nov. 29, 1968, Nov. 29, 1968, Nov. 29,

1968 Japan 43/87,430, 43/104,129 and 43/104,130

ELECTRIC SNAP SWITCH 13 Claims, 14 Drawing Figs.

US. Cl 335/205, 200/67 F lnt. Cl I-I0lh 5/02, HOlh 5/04, l-lOlh 5 H28 Field of Search 200/67 F;

[56] References Cited UNITED STATES PATENTS 3,233,061 2/1966 Jones, Jr

3,486,144 12/1969 Paige Primary Examiner- Bernard A. Gilheany Assistant Examiner-R. N. Envall, Jr. Attorney-Craig, Antonclli, Stewart & Hill 200/67 F X 200/67 F X durance of the switch.

PATENTEI] 111:1 51911 SHEET 2 OF 4 FIGS FIG.6

iNVENTOR YAS HIKG wnMI ATTORNEY PATENTEU 151 51911 SHEET & BF 4 FIGS FIG.|0(A) INVENTOR ynsuurxo 1W4 M I BY M -yaw. 7' ATTORNEYS ELECTRIC SNAP SWITCH The present invention relates to an electric snap switch and, more particularly, to a magnetically operated reed switch having a snap-acting mechanism for rapidly shifiing a permanent magnet to instantly open and close the reed switch.

It has been well known that an improved switch with respect to performance and endurance should be used in control function of the switch mechanism is an important factor. For this reason, of various switches heretofore developed a reed switch has been employed in the art because of its satisfaction of the requirement. As is well known, a reed switch is provided with switching contacts disposed within a glass tube filled with an inert gas, and has the advantage that the service life of the contacts is substantially improved.

Such a reed switch now employed in the art has a function characterized in that, a pair of contacts thereof in the open condition are formed into magnetic poles of opposite polarity respectively, when a magnetic field is generated about said contacts by means of a permanent magnet or an electromagnet, and subsequently, commence to attract each other to establish the closed condition in said switch.

The present invention and the prior art will be hereinafter fully described with reference to the accompanying drawings, showing some embodiments of the present invention only for the purpose of explanation thereof, and wherein:

FIG. 1(A) and (B) are schematic diagrams showing a conventional magnetically operated reed switch;

FIG. 2( A) and (B) are schematic diagrams showing a magnetically operated reed switch according to the present invention;

FIG. 3 is a graph illustrating a magnetic characteristic as function of the magnetic flux density M in a reed switch and the stroke K of a permanent magnet;

FIG. 4 is a graph illustrating the operational characteristic of a snap-acting mechanism relating the stroke T to the operating force of the movable member;

FIG. 5 is a side view, constituting a plane section through the cover-housing interface, of an electric snap switch showing one modification of the present invention;

FIG. 6 is an isometric view of parts of the electric snap switch shown in FIG. 5;

FIG. 7(A) and (B) are schematic diagrams illustrating the operation of the electric snap switch of FIG. 5;

FIG. 8 is a side view constituting a plane section through the cover-housing interface, of an electric snap switch showing another modification of the present invention;

FIG. 9 is an isometric view of parts of the electric snap switch shown in FIG. 8; and

FIG. 10(A) and (B) are schematic diagrams illustrating the operation of the electric snap switch of FIG. 8.

In order to make the most of such a function of the reed switch, a conventional type of reed switch has been designed as illustrated in FIG. 1 with a vertically movable permanent magnet 2 being positioned just above the reed switch 1 of which a glass tube has a pair of horizontally elongated reeds la and lb provided with contacts laand lbat the oppositely adjacent ends thereof, so that the contacts la and lb are en gaged together to make the circuit when the permanent magnet 2 is brought close downwardly to the reeds la and lb, to such an extent that the magnetic flux produced by said permanent magnet 2 effects said reeds la and lb, and, on the other hand, when the magnet 2 is displaced upwardly from said reeds la and lb to such an extent that said magnetic flux which has been effecting the reeds la and lb extinguishes, the contacts la and lb are disengaged from each other to break the circuit.

However, in such a type of reed switch as described above, there has been found a defect that a relatively greater stroke is necessary to shift the permanent magnet 2 from a position close to the horizontally laid switch 1, so as to cause its contacts la and lb to be engaged by means of the effective magnetic flux D produced by the magnet 2 in the horizontal direction, to another position away from said switch 1 so as to cause its contacts la and lb to be disengaged by means of the effective resilience force possessed in the reeds la and lb, and vice versa, resulting in that the switching operation of the contacts 1a and lb tends to become loose. FIG. 3 shows the magnetic characteristic of the magnetic flux density M in relation to the stroke K in which the permanent magnet is moved in the transverse direction substantially at a right angle to the lengthwise direction of the reed switch. In FIG. 3 a curve of comparatively small inclination as indicated by X designates the stroke of a conventional type of the reed switch I. As is apparent from the characteristic curve X, the stroke S of the magnet from the position P representing a value-of the magnetic flux density necessary to close the reed switch 1, to another position 0, representing a value of the magnetic flux density necessary to open the reed switch 1 is of comparatively great value as indicated by 8,.

As one method to eliminate the above-mentioned defect, it has been contemplated to provide a snap-acting mechanism to the reed switch wherein the permanent magnet is fitted to a quick motion member of the snap-acting mechanism so that a snap action of the snap-acting mechanism may be applied to shift the permanent magnet from the position P to the position 0,. A shifting stroke of the quick motion member of such snap-acting mechanism, that is, the stroke of the permanent magnet, depends upon the operational characteristic of the snap-acting mechanism relating to the stroke T and the operating force 0 of the quick motion member as shown in FIG. 4.

In the construction of the reed switch thus provided with the snap-acting mechanism the magnitude of the shifiing stroke of the quick motion member necessary to operate the reed switch corresponds to the hereinbefore described value 8,. Since it is apparent that the distance of travel of the quick motion member from the free position to the operating position (which distance being hereinafter referred to as P.T.") and the value S of the shifting stroke of the permanent magnet are in the proportional relationship, the magnitude of RT. should be sufficient to correspond to the value 8,. In addition thereto, the distance of return travel of the quick motion member from the operating position to the free position (which distance being hereinafter referred to as R.T.) should be of a value approximate to that of RT. Therefore, this results in the increase of a the value of the distance of movement difference of the quick motion member from the operating position to the release position (which distance being hereinafter referred to as M.D.

Accordingly, in the reed switch of such construction, without permitting an increase in the distance MD. of the snap-acting mechanism it is impossible to operate the reed switch. However, increase of the distance MD. may result in that a rapid switching operation of the reed switch cannot be performed by means of the snap action of the snap-acting mechanism. Furthermore, an operating force of large magnitude, (which force being hereinafter referred to as O.P.") necessary to cause contact snap action to operate the reed switch, in accordance with increase of the distances P.T. and MD. will be necessary and subsequently constitute a cause for fatigue of the switching mechanism of the reed switch due to the amplitude of stress developed. Therefore, the life of service of the reed switch of such construction may be shortened and, because of the great stroke required in connection with the quick motion member of the snap-acting mechanism, the size thereof must be increased in order to accommodate said mechanism in the reed switch assembly.

These and other defects of the conventional reed switch as hereinbefore described have been eliminated in the present invention.

A primary object of the present invention is to provide an electric snap switch of the above character having the snapacting mechanism, whereby the permanent magnet is horizontally moved in the lengthwise direction of the reed switch, that is, the same direction of horizontally elongated reeds la and 1b, by means of the snap action of said mechanism to operate rapidly said reed switch in an improved manner.

In the electric snap switch of the present invention, shown in FIGS. 2 (A) and 2 (B), a reed switch 7 is always positioned within an effective magnetic flux path formed by a permanent magnet 6, so that switching contacts 70 and 7b of the horizontally laid reed switch 7 are disengaged each other to break the circuit, by applying the vertically generated effective magnetic flux b thereto, and, when the permanent magnet 6 is snapped by means of the snap-acting mechanism, until the horizontally generated effective magnetic flux 1 is applied to the switching contacts 7a and 7b, the contacts 7a and 7b are engaged to make the circuit by said flux I In other words, referring to FIG. 2 showing such a magnetically operated reed switch, the permanent magnet 6 is disposed at one position, for example, at the left-hand position of the reed switch 7 in FIG. 2(A) to apply the vertically generated efiective magnetic flux I to the switching contacts 7a and 7b and the permanent magnet 6 may be displaced in the lengthwise direction of and in the parallel relation to the reed switch 7 to another position, for example, just above the switch 7 in FIG. 2(B) where the horizontally generated effective magnetic flux 1 is applied to the switching contacts 7a and 7b. Such reciprocation of the permanent magnet 6 for operating the reed switch 7 can be rapidly performed by means of the snap-acting mechanism with substantial reduction of a value of the shifting stroke of the permanent magnet 6.

According to the reed switch hereinbefore described with reference to FIG. 2(A), the characteristic curve of the magnetic flux density relative to the stroke of the permanent magnet 6 to be moved in the horizontal direction in substantially parallel relation to the lengthwise direction of the reed switch 7 is shown by Y in FIG. 3. It is apparent from the characteristic curve Y, of comparatively large inclination, that the stroke of the permanent magnet 6 from a position P, representing a value of the magnetic flux density necessary to close the reed switch 7, to another position Q representing a value of the magnetic flux density necessary to open the operation of the reed switch 7, has a reduced value as indicated by 8,, in comparison with the above-mentioned stroke S, of the curve X. Therefore, the shifting stroke of the quick motion member of the snap-acting mechanism fitted with the permanent magnet 6 can be determined to a corresponding value of a small stroke of the permanent magnet 6. In proportion thereto, a value of the distances P.T. and RT. of the snapacting mechanism can be respectively reduced, so that a value of the distance M.D. can be subsequently reduced, to perform a rapid switching operation of the reed switch 7, resulting in the improved sensitivity and endurance of the electric snap switch having the snap-acting mechanism, for rapidly shifting a permanent magnet to instantly open and close the reed switch 7.

The heretofore described snap-acting mechanism to be used with a magnetically operated reed switch of the present invention is generally provided with a tension element and a compression element which are arranged to moved quickly at dead-center connection therebetween and includes a so-called semisnap-acting mechanism, which is provided with a quick motion member to be moved merely by presenting it. Said quick motion member is also represented as one of the movable members of said snap-acting mechanism and includes another acting means associated with said quick motion members.

The shifting direction of the permanent magnet to be moved by the snap-acting mechanism in parallel relation to the lengthwise direction of the reed switch may be alternatively in the direction of arc, but horizontally in parallel relation thereto. The reed switch of the type having a pair of reeds provided with a contact may include a reed switch of the transfer type, having three reeds of which the movable contact engages always one of other contacts.

Another-object of the present invention is to provide an electric snap switch having a snap-acting mechanism, comprising a quick motion member of which one end is pivotally engaged to a fitting position and the other end is pivotally promotion member, an actuator member of which one end is free to operate and the other end is pivotally engaged to a fitting position, said actuator member being engaged at its predetermined position with the other end of said compression elements, and a plunger member disposed adjacent to the free end of said actuator member, said quick motion member, compression element and actuator member being constituted a snap-acting mechanism to be performed a snap action by which said magnet is quickly moved in the lengthwise direction of and in parallel to the reed switch so as to operate said switch. By achieving this object, the size of the magnetically operated reed switch of the present invention can be reduced because the magnet can be quickly moved by the snap acting mechanism in a small spacing.

A further object of the present invention is to provide a magnetically operated reed switch having means for operating the magnet to open and close the reed switch, that is, the quick motion member, wherein said magnet is supported by said means through the magnetic attraction acting between said magnet and a plate member of magnetic material effective to shield the reed switch from the influence of ma external magnetic field. With this provision, the magnet can be reliably supported by said simple supporting means to be efiected with an operating force of the plunger member.

A still further object of the present invention is to provide an electric snap switch having a magnet to open and close the reed switch comprising a resilient member of magnetic material which one end is fixed and the other end is a free end opposed to one pole of said magnet in such a manner that said free end is attracted or released from the attraction of said magnet to provide the semiquickness of operation of the reed switch.

With this resilient member of magnetic material and the magnet, the electric snap switch having a means for suggesting a sensory representation of the switching condition to the operator can be obtained. In addition thereto, a novel construction of the magnetically operated reed switch operable in a semiquick action can be obtained. In connection with one embodiment as illustrated in FIG. 5 to FIG. 7, a housing 10 is accommodated with a snap-acting mechanism and a reed switch assembly to be operated thereby.

A quick motion member 12 of the snap-acting mechanism is formed roughly with the shape of B, an top end 120 of which is pivotally engaged in a recessed portion 10a formed on the housing 10 at a position C while the bottom end 12b thereof is pivotally engaged in a notched groove 13a formed at the bottom of a permanent magnet 13 and the middle end 120 is pivotally connected to one end 14a of a compression element 14 made of a leaf spring at a position D.

An actuator member 15 of the snap-acting mechanism is formed roughly in the shape of an L, one end 150 of which is pivotally engaged at a position E to a notch 160 on a first stationary member 16 while the other end 15b thereof is free to operate. The other end 14b of the compression element 14 is engaged at a position F to a notch formed about an intermediate position between the opposite ends 15a and 15b.

The first stationary member 16 fixed in the housing 10 is provided with stopper portions 16b and 16c for defining a movement range of the quick motion member 12, one end 16d being formed as a supporting end for supporting a reed 17a extending from one end of a reed switch 17 while the other end l6e thereof being formed as a terminal an outside electric connection. I

Both the compression element 14 and the actuator member 15 form a snap-acting mechanism of which the dead line L exists between the engagement positions C and D respectively on the quick motion member 12 and the compression element 14 as shown in FIG. 7.

A plunger member 18 having a head portion at one end thereof in contact with the free end 15b of the actuator member 15 within the housing is reciprocable through the aperture of the housing and is operable by pressing the outer portion of its other end. One end 190 of a second stationary member 19 is formed in an upright position to serve as a supporting end for supporting a reed 17b extending from the other end of the reed switch 17 while the other end 19b thereof is formed as a terminal for an outside electric connectron.

Although in this first embodiment of the present invention the compression element 14 is formed independently of the other elements or members and engaged at its end 140 to the engagement portion 120 on the quick motion member 12, said compression element 14 may be integrally formed with the quick motion member 12 in such a manner as to elongate the engagement portion 12c in the fonn of a tongue. Therefore, if the compression element 14 is the form of the tongue integrally elongated from the engagement portion 12c of the quick motion member 12 is employed, engagement of the compression element 14 to the quick motion member 12 will be an integral connection which may be employed.

The magnet 13 is provided at its bottom side with a notched groove 13a to which the L-shaped end 12b of the quick motion member 12 is pivotally engaged. A fixed plate 11 of magnetic material shaped in the L-form is provided with a bottom side 11:: in contact with the bottom wall of the housing and a lateral side 11a adjacent to a side wall of the housing 10 and serves to shield the reed switch 17 from the influence of an external magnetic force and also to support the magnet 13 in the desired posture by means of the magnetic attraction acting between the magnet 13 and the bottom side 11a lateral side 11b while the magnet 13 is carried by the L-shaped end 12b of the quick motion member 12 engaging in its notched groove 130. Therefore, no special provision for supporting the magnet 13 is required in this instance. In addition thereto, said fixed plate also serves as a means for shielding the reed switch assembly form the influence of an external magnetic force and no additional provision for the same purpose is required.

The operation of the reed switch assembly of the above con struction is as follows: Referring now to FIG. 7(A) and (B), when in the nonoperated condition, the magnet 13 is positioned to the left side of the reed switch 17 and the magnetic flux l generated by said magnet 13 as illustrated in FIG. 2(A) is at this time set up vertically in the reeds 17a and 17b of the reed switch 17 so as to open the circuit.

When the plunger member 18 is depressed by the pressing force of a operator as shown in FIG. 7(B), the actuator member 15 is swung in the counterclockwise direction around the engagement position E which, at this time, serves as a fulcrum of the notch 16a of the first stationary member 16. At the same time as the actuator member 15 is swung in said direction, the engagement position F engaged to the compression element 14 travels upwardly to the left to cause the compression element 14 to accumulate a resilient force therein, the value of said resilient force arriving at its maximum value when the engagement position F is positioned on the dead line L passing between the engagement positions C and D.

As the plunger member 18 is depressed until the engagement position F pass beyond the dead line L, the resilient force accumulated in the compression element 14 is instantly released accompanying a rapid swing of the quick motion member 12 in the counterclockwise direction around the engagement position C in a recessed portion 100 of the housing 10. Thus the magnet 13 is moved to the right to position it in the center of the reed switch 17, as shown in FIG. 7(B) to establish the condition of the magnet 13 as illustrated in FIG. 2(B) in which the magnetic flux by said magnet 13 is at this time set up horizontally in the reeds 17a and 17b and thereby to close the circuit.

When the plunger member 18 is released from the depressed condition, the arrangement of the parts is returned to the initial condition in the reverse manner to open the circuit by means of the self-restoring force of the snap-acting mechanism.

It is apparent from the foregoing description of the electric snap switch of the present invention in connection with the first embodiment thereof that the distance MD. is substantially reduced with improved sensitivity and endurance. Therefore, by incorporating various features of the present invention, the size of the switch can also be reduced.

Now, to the second embodiment of the present invention with reference to FIG. 8 to FIG. 10, a housing 20 is accommodated with a semisnap-acting mechanism and a reed switch assembly to be operated thereby. A stationary member 2] fixed in the housing 20is provided with an end portion 210 formed as a terminal for outside electric connection. The other end portion of said stationary member 21 is, as shown in FIG. 9, provided with a pair of supporting holes 21a,, an open slot 2la for defining a movement range of a quick motion member 23, leglike portions 210 defining said open slot 2111,, and a supporter lug 21b for supporting a reed 24a extending from one end of a reed switch 24. Provided between the leglike portions 210 and the terminal end 210 is a hooklike lug 21d for retaining one end of a tension spring 22. A quick motion member 23 of the semiquick-acting mechanism is provided with a pair of lugs 230 which are in turn pivotally engaged at a position G to the corresponding supporting holes 21a, disposed on the leglike portion 21a of the stationary member 21. The opposite end 23b formed in the L-shape of the quick motion member 23 is pivotally engaged to a notched groove 25a formed on the bottom side of the magnet 25 in the same manner as in the first embodiment so as to carry the magnet 25 by the quick motion member 23. The magnet 25 is disposed so as to render its lengthwise direction in parallel relation to that of the reed switch 24 having a pair of reeds 24a and 24b.

The quick motion member 23 is also provided with an operating element 230 formed by bending an intermediate portion thereof at right angle as shown in FIG. 9, one end of which is free end to be depressed by means of a plunger member 28 while the other end thereof is provided with a hooklike lug 23d for retaining the other end of the tension spring 22. One end 26a of a second stationary member 26 fixed in the housing 20 is formed in an upright position to serve as a supporting end for supporting a reed 24b extending from the reed switch 24, while the other end 26b thereof is formed as a terminal for an outside electric connection. The reed switch 24 is supported between the end 260 of the second stationary member 26 and the supporting lug 21b of the first mentioned stationary member 21 in such a manner that the reed 24a is connected to the supporting lug 21b and the reed 24b is connected to the supporting end 26b by soldering or suitable means.

A resilient member 27, made of magnetic material, of the semiquick-acting mechanism is provided with an end 27a secured at a position H to the top wall of the housing 20 and a free end 27b shaped in the L-form. The free end 27b of said resilient element 27 is normally attracted to one pole of the magnet 25, and said resilient element 27 acts in cooperation with the magnet 25 as an element for suggesting a sensory representation of the switching condition to the operator.

Both the tension spring 22 and the quick motion member 23 and the resilient member 27 form a semisnap-acting mechanism of which the dead point exists, at the moment the attracted relationship between said member 27 and magnet 25 is released in connection with the pushing force of said spring 22 as shown in FIG. 10.

A plunger member 28 having a head portion at one end thereof in contact with the free end of the operating element 230 of the quick motion member 23 within the housing 20 is reciprocable through the aperture of the housing to operate by pressing the outer portion of its other end.

The operation of the reed switch assembly of the above construction is as follows. Referring now to FIG. 10, when in the nonoperated condition, the free end 27b of the resilient member 27 is, as shown in FIG. 10(A), in the attracted condition to one pole of the magnet 25 and the magnetic flux 17,

generated by said magnet 25 as illustrated in FIG. 2(A) is at this time set up vertically in the reeds 24a and 24b of the reed switch 24 so as to open the circuit.

When the plunger member 29 is depressed by the pressing force of a operator against the resilient force of the tension spring 22 as shown in FIG. (8), the quick motion member 23 is swung in the counterclockwise direction around the engagement position G which, at this time serves as a fulcrum, thereby to move the magnet 25 to the right in parallel to the lengthwise direction of the reed switch 24. During the movement of the quick motion member 23 and subsequently the magnet 25 to the right, the resilient member 27 is also swung in the counterclockwise direction around the fixed position H while being attracted by one pole of the magnet 25. However, as the intrinsic resilient force of the resilient element 27 bears against the attracting force of the magnet 25, the attracted relationship between said element 27 and magnet 25 is released in a semiquick action whereby a retaining force of the quick motion member 23 effected on the plunger member 29 is reduced while the magnet 29 further moves to the right until the magnetic flux 1 generated thereby is set up horizontally in the reeds 24a and 24b of the reed switch 24, and thereby to close the circuit as shown in FIG. 10(B).

When the plunger member 29 is released from the depressed condition, the quick motion member 23 is returned by the resilient force of the tension spring 22 to the position in which, in addition to said resilient force of the spring 22, the one pole of the magnet 25 commences to attract the resilient element 27, resulting in that the arrangement of the semisnapacting mechanism is substantially returned to the initial condition in the reverse manner to open the circuit. Even at this time, the semiquick action of the switch can obtained.

Although the present invention has been heretofore fully described in connection with the first and second embodiments thereof with reference to the accompanying drawings, it is understood that the same is not limited thereto but is susceptible to numerous changes and modifications as known to a person skilled in the art and we, therefore, do not wish to be limited to the details shown and described herein, but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

What is claimed is:

1. An electric snap switch comprising an overcenter snap-acting mechanism, having a quick motion member, one end of which is supported by a tension member and the other end of which is supported by a compression member,

a permanent magnet being engaged to move together with said quick motion member by means of the magnetic attraction of a fixed magnetic plate effective to shield said reed switch from the influence of an external magnetic field, and

a reed switch having a pair of elongated reed-type switching contacts operated by the magnetic flux of said magnet, and wherein said magnet is moved in parallel to the longitudinal direction of said reeds from a position in which the flux of said magnet is set up vertically on said contacts to open said contacts to the position in which the flux of said magnet is set up horizontally on said contacts to close said contacts.

2. An electric snap switch comprising an overcenter snap-acting mechanism having a magnetic resilient member of which one end is fixed at a first position and the other end is opposed to one pole of a permanent magnet, said magnet being moved quickly by means for suddenly removing magnetic attraction between said resilience member and magnet,

a reed switch having a pair of elongated reed-type switching contacts operated by the magnetic flux of said magnet, and wherein said magnet is moved in parallel to the longitudinal direction of said reeds.

3. An electric switch comprising:

a reed switch having a plurality of elongated reed switching contacts which close in response to the application of a magnetic field thereto;

a permanent magnet, displaceable with respect to said reed switch in a direction parallel to the longitudinal direction of the elongated reed contacts thereof; and

an overcenter snap-acting mechanism connected to said magnet for rapidly displacing said magnet with respect to said reed switch contacts so as to open and close said contacts.

4. A switch in accordance with claim 3, wherein said magnet occupies a first position in said switch with respect to said reed contacts, whereby the flux produced by said magnet passes substantially transversely with respect to the longitudinal direction of said contacts, and upon displacement with respect to said reed contacts, occupies a second position with respect to said reed contacts, whereby the flux produced by said magnet passes substantially parallel with respect to the longitudinal direction of said contacts.

5. A switch in accordance with claim 4, wherein said switch further includes a housing, and said overcenter snap-acting mechanism includes a quick motion member, one end of which is pivoted about a first position within said housing and the other end of which is engaged with said magnet, an actuator member, one end of which is pivoted about a second position within said housing, while the other end is freely displaceable, a compression member, one end of which is pivotally engaged at an intermediate portion of said quick mo tion member and the other end of which is pivotally engaged at an intermediate portion of said actuator member.

6. An electric switch comprising:

a housing;

a reed switch supported within said housing and having a plurality of elongated reed switching contacts which close and open in response to the application and removal, respectively, of'a magnetic field thereto;

a permanent magnet, supported within said housing and being displaceable with respect to said reed switch in a direction parallel to the longitudinal direction of said elongated contacts of said reed switch; and

an overcenter snap-acting mechanism connected to said magnet for rapidly displacing said magnet with respect to said reed switch contacts, so as to open and close said contacts, said overcenter snap acting mechanism comprising a quick motion member having a first end, an interior portion and a second end, said quick motion member being pivoted at its first end about a first position within said housing and being engaged at its second end, with said magnet; V

an actuator member having a first end, an interior portion and a second end, said actuator member being pivoted at its first end at a second position within said housing and having its second end reciprocally displaceable by a plunger member disposed within said housing;

a compression member having a first end and a second end, said compression member being pivotally engaged at its first end with the intermediate portion of said quick motion member and being pivotally engaged to the intermediate portion of said actuator member at its second end.

7. A switch in accordance with claim 6, further including a first stationary member disposed within said housing for supporting one end of said reed switch and for pivotally supporting the second end of said actuator member, and a second stationary member for supporting the other end of said reed switch, each of said first and second stationary members being conductive and formed to provide external electrical connections for said reed switch.

8. An electric switch comprising:

a snap-acting mechanism having a quick motion member quickly displaceable in one direction;

a reed switch having a pair of elongated reed contacts, the

closure of which is effected by the application of a magnetic field thereto; and

means for effecting the application of a magnetic field to said reed contacts, while shielding said contacts from the influence of a magnetic field external to said switch, including a permanent magnet pivotally supported by said quick motion member and being displaceable in a direction parallel to the longitudinal direction of said elongated reed contacts, and a fixed magnetic plated supported adjacent said magnet, whereby, the magnetic flux for closing said contacts emanates from said plate in cooperation with said magnet.

9. An electric switch comprising:

a housing;

a reed switch supported within said housing and having a plurality of elongated reed switching contacts which close and open in response to the application and removal, respectively, of a magnetic field thereto;

a permanent magnet supported within said housing and being displaceable with respect to said reed switch in a direction parallel to the longitudinal direction of said elongated contacts of said reed switch; and

an overcenter snap-acting mechanism connected to said magnet for rapidly displacing said magnet with respect to said reed switch contacts, so as to open and close said contacts, said overcenter snap-acting mechanism comprising:

a quick motion member having a first portion and an operating second portion;

a resilience member, coupled to said quick motion member and being pivotally engaged at one end thereof with said housing, and being magnetically coupled to one end of said magnet at the other end thereof; and

means, engaged with said quick motion member and said housing, for suddenly removing the magnetic coupling between said resilient member and said magnet.

10. A switch in accordance with claim 9, wherein said means for suddenly removing the magnetic coupling includes a tension spring connected at one end thereof to said housing and at the other end thereof to said second portion of said quick motion member, and a plunger element engagingly coupled to said first portion of said quick motion member.

11. A switch in accordance with claim 10, further including a first stationary member disposed within said housing for conductively engaging one end of said reed switch and for pivotally supporting said quick motion member and a second stationary member for supporting the other end of said reed switch, each of said first and second stationary members being conductively formed to provide the external electrical connections for said reed switch.

12. A switch in accordance with claim 6, wherein said quick motion member is substantially E-shaped.

13. A switch in accordance with claim 12, wherein said actuator member is substantially L-shaped. 

1. An electric snap switch comprising an overcenter snap-acting mechanism, having a quick motion member, one end of which is supported by a tension member and the other end of which is supported by a compression member, a permanent magnet being engaged to move together with said quick motion member by means of the magnetic attraction of a fixed magnetic plate effective to shield said reed switch from the influence of an external magnetic field, and a reed switch having a pair of elongated reed-type switching contacts operated by the magnetic flux of said magnet, and wherein said magnet is moved in parallel to the longitudinal direction of said reeds from a position in which the flux of said magnet is set up vertically on said contacts to open said contacts to the position in which the flux of said magnet is set up horizontally on said contacts to close said contacts.
 2. An electric snap switch comprising an overcenter snap-acting mechanism having a magnetic resilient member of which one end is fixed at a first position and the other end is opposed to one pole of a permanent magnet, said magnet being moved quickly by means for suddenly removing magnetic attraction between said resilience member and magnet, a reed switch having a pair of elongated reed-type switching contacts operated by the magnetic flux of said magnet, and wherein said magnet is moved in parallel to the longitudinal direction of said reeds.
 3. An electric switch comprising: a reed switch having a plurality of elongated reed switching contacts which close in response to the application of a magnetic field thereto; a permanent magnet, displaceable with respect to said reed switch in a direction parallel to the longitudinal direction of the elongated reed contacts thereof; and an overcenter snap-acting mechanism connected to said magnet for rapidly displacing said magnet with respect to said reed switch contacts so as to open and close said contacts.
 4. A switch in accordance with claim 3, wherein said magnet occupies a first position in said switch with respect to said reed contacts, whereby the flux produced by said magnet passes substantially transversely with respect to the longitudinal direction of said contacts, and upon displacement with respect to said reed contacts, occupies a second position with respect to said reed contacts, whereby the flux produced by said magnet passes substantially parallel with respect to the longitudinal direction of said contacts.
 5. A switch in accordance with claim 4, wherein said switch further includes a housing, and said overcenter snap-acting mechanism includes a quick motion member, one end of which is pivoted about a first position within said housing and the other end of which is engaged with said magnet, an actuator member, one end of which is pivoted about a second position within said housing, while the other end is freely displaceable, a compression member, one end of which is pivotally engaged at an intermediate portion of said quick motion member and the other end of which is pivotally engaged at an intermediate portion of said actuator member.
 6. An electric switch comprising: a housing; a reed switch supported within said housing and having a plurality of elongated reed switching contacts which close and open in response to the application and removal, respectively, of a magnetic field thereto; a permanent magnet, supported within said housing and being displaceable with respect to said reed switch in a direction parallel to the longitudinal direction of said elongated contacts of said reed switch; and an overcenter snap-acting mechanism connected to said magnet for rapidly displacing said magnet with respect to said reed switch contacts, so as to open and close said contacts, said overcenter snap acting mechanism comprising a quick motion member having a first end, an interior portion and a second end, said quick motion member being pivoted at its first end about a first position within said housing and being engaged at its second end, with said magnet; an actuator member having a first end, an interior portion and a second end, said actuator member being pivoted at its first end at a second position within said housing and having its second end reciprocally displaceable by a plunger member disposed within said housing; a compression member having a first end and a second end, said compression member being pivotally engaged at its first end with the intermediate portion of said quick motion member and being pivotally engaged to the intermediate portion of said actuator member at its second end.
 7. A switch in accordance with claim 6, further including a first stationary member disposed within said housing for supporting one end of said reed switch and for pivotally supporting the second end of said actuator member, and a second stationary member for supporting the other end of said reed switch, each of said first and second stationary members being conductive and formed to provide external electrical connections for said reed switch.
 8. An electric switch comprising: a snap-acting mechanism having a quick motion member quickly displaceable in one direction; a reed switch having a pair of elongated reed contacts, the closure of which is effected by the application of a magnetic field thereto; and means for effecting the application of a magnetic field to said reed contacts, while shielding said contacts from the influence of a magnetic field external to said switch, including a permanent magnet pivotally supported by said quick motion member and being displaceable in a direction parallel to the longitudinal direction of said elongated reed contacts, and a fixed magnetic plated supported adjacent said magnet, whereby, the magnetic flux for closing said contacts emanates from said plate in cooperation with said magnet.
 9. An electric switch comprising: a housing; a reed switch supported within said housing and having a plurality of elongated reed switching contacts which close and open in response to the application and removal, respectively, of a magnetic field thereto; a permanent magnet supported within said housing and being displaceable with respect to said reed switch in a direction parallel to the longitudinal direction of said elongated coNtacts of said reed switch; and an overcenter snap-acting mechanism connected to said magnet for rapidly displacing said magnet with respect to said reed switch contacts, so as to open and close said contacts, said overcenter snap-acting mechanism comprising: a quick motion member having a first portion and an operating second portion; a resilience member, coupled to said quick motion member and being pivotally engaged at one end thereof with said housing, and being magnetically coupled to one end of said magnet at the other end thereof; and means, engaged with said quick motion member and said housing, for suddenly removing the magnetic coupling between said resilient member and said magnet.
 10. A switch in accordance with claim 9, wherein said means for suddenly removing the magnetic coupling includes a tension spring connected at one end thereof to said housing and at the other end thereof to said second portion of said quick motion member, and a plunger element engagingly coupled to said first portion of said quick motion member.
 11. A switch in accordance with claim 10, further including a first stationary member disposed within said housing for conductively engaging one end of said reed switch and for pivotally supporting said quick motion member and a second stationary member for supporting the other end of said reed switch, each of said first and second stationary members being conductively formed to provide the external electrical connections for said reed switch.
 12. A switch in accordance with claim 6, wherein said quick motion member is substantially E-shaped.
 13. A switch in accordance with claim 12, wherein said actuator member is substantially L-shaped. 